Experimental investigation of single microdischarges in a barrier corona arrangement with a cathodic metal pin

Abstract

Microdischarges (MDs) in a sinusoidally driven barrier corona discharge, operated in dry air at atmospheric pressure, are investigated using time-correlated single photon counting (TC-SPC) technique, electrical measurements (applied voltage and current pulses) and ICCD images. In the current contribution, results of the cathodic pin half-cycle are presented. Results of the anodic pin half-cycle were presented in a previous study (Jahanbakhsh et al 2018 Plasma Sources Sci. Technol. 27 115011). In the cathodic pin half-cycle appearance phase and current pulse amplitude of the MDs have an erratic behavior. Hence, a statistical study of the current pulse amplitudes is conducted, and it is correlated to the phase-resolved spatio-temporal development of the MDs, obtained from TC-SPC recordings. This study indicates that the breakdown and development of the MDs is dependent on their inception phase, which is related to the discharge activity in preceding (anodic pin) halfcycles. It is shown that the MDs appearing at lower applied voltages are ignited with a positive streamer starting near the anode (dielectric), similar to single dielectric barrier discharge MDs. On the other hand, the inception of the MDs appearing at higher applied voltages takes place with a double-streamer mechanism starting near the tip of the cathode (pin). These MDs have similarities to transient sparks, in particular much higher current pulse amplitudes compared to single DBDs.

A spectral element method for modelling streamer discharges in low-temperature atmospheric-pressure plasmas

“…The main advantage of the proposed simulation scheme is its flexibility and potential ability to simulate plasma discharges in complex geometries. For example, after further development, the method can be applied to complement current experimental studies on nanosecond pulsed streamer discharges [37,38,39] or reveal discharge properties for novel plasma jet devices [40]. The flexibility of the HPS scheme can be utilized to develop a decomposition technique for resolving boundary layers on the electrode surfaces with high accuracy.…”

“…where it is taken into account that g 4 from expressions (39) for α ∈ {1, 3, 4} with k = a and for α ∈ {1, 2, 3} with k = b, respectively. In this way, it is possible to construct the set of mappings that transform the potential on the boundary of Ω c to the vectors n…”

“…The global solution operator must be newly constructed every time the mesh or charge distribution are changed. When only the charge distribution is changed, there is only need to update the translation vectors in the DtN operators (i. e., r (k) α in (39)). In this case, we say that the global solution operator is updated rather than constructed.…”

Experimental and simulated investigation of microdischarge characteristics in a pin-to-pin dielectric barrier discharge (DBD) reactor

“…In the plasma zone, a grid with 450 elements is adopted. The electron density varies drastically near the boundary between the plasma zone and the solid [18]. Therefore, the smallest mesh is adopted at the interface between the solid and plasma region to obtain more accurate results.…”

“…Although the occurrence of MD seems to be temporally and spatially disordered, the appearance of MD repeats within a fixed area for hundreds of half-periods (HPs) caused by the residual charges in the discharge zone and on the dielectric surface during the dielectric barrier discharge (DBD) process [15,16]. Recently, researchers have investigated the effects of the gas composition, the shape of the applied voltage, and the arrangement of the DBD reactor on the features of MDs, such as the radius of the discharge channel, the streamer velocity, and the discharge current [17][18][19][20][21][22][23]. Despite the investigation into the MD's features in previous studies, it is still necessary to conduct further research into the behaviors of an individual MD to develop an efficient and suitable DBD reactor.…”